Edwin j



(No Model.)

B. J. ARMSTRONG.

GRINDING MACHINE. No. 375,247. Patented Dec. 20, 1887.

WITNESSES I VENTOR. z dwcn Z1y6w N. PETERS. 'Phulrrlitmgnphon Wahin ppppp t;

I UNITED STATES PATENT OrricE.

EDWINJ. ARMSTRONG OF PAINTED POST, N YORK.

GRlNDlNG- MACHINE.

SPECIFICATION forming part of Letters Patent No. 375,247, dated December 20, 1887.

Application filed April 30, 1887. Serial No. 236,687. (No model.) I

the artto which it appertains to make and use the same.

My invention relates to that class of toolgrinding machines in which a revolving grindstone or disk is employed; and it has for its ob ect to provide a tool-rest in which that edge of the rest-plate next to the periphery of the stone or grinding-disk will at all times retain its set proximity to said stone, no matter what the angle of adjustment of the rest-plateproper may be, and also to simplify the adjusting mechanism and produce a simple, easily and quickly operated, and accurately-adjustable tool-rest of but few parts; and it consists of the parts and combinations of parts hereinafter described and claimed.

In the accompanying drawings, forming a part of this specification, Figure 1 is a side elevation of a grinding-machine having my improved rest, the latter partly in section, attached thereto; Fig. 2, afront elevation, partly in section; and Fig. 3, a detail perspective view of the rest-plate and attached parts.

Similar letters refer to similar partsin all the vlews.

A represents a suitable frame, of cast-iron, wood, or any other desired material, from which projects anu'pright, A, havinga suitable hearing in its upper end for the shaft of the stone or disk B. The frame is suitably supported on legs a, and is provided with a horizontallyprojecting beam, 0, for the purpose of supporting my improved tool-rest device. To this beam 0, I secure, by means of bolts or otherwise, one end of a bar or arm, D, which pro- 5 jects at right angles or laterally, and curves upwardly from said beam across the periphery of the stone and extends some distance beyond the side of said stone. The upper end of this arm has cast or otherwise rigidly secured to it a curved plate or support, E, which extends at right angles and rearwardly from said arm,

curving upward. In this plate I form a slot, b, and a recess or groove, 0, as clearly shown in Figs. 1 and 2. On the flat side or surface of a semicircular tilting or pivot block, F, is cast or otherwise rigidly secured a rest-plate, G, the inner edge of said plate being on aline with the axis of the block and the upper surface of the plate on substantially the same plane as the upper or flat surface of the block. This rest-plate extends across and beyond the periphery of the stone or disk on both sides, and has its edge h chamfered, as clearly shown in Figs. 1 and 3, the-block F being toone side of said stone. The semicircular block F has formed on its rear side a central projection or offset, f, extending from end to end of the rounded portionof the same. An eyebolt, g, is screwed into or otherwise firmly secured to the block F in the center of the offset f and projects downwardly therefrom. The block F rests on the side flanges of the support E, and its offset or projection f in the recess or groove 0 of said support, the eyebolt 9 pass ing through the slot 12 in the block, as clearly shown in Fig. 1, so that the eyebolt may be moved in the slot longitudinally or in the direction of length of said slot, and thus tip the rest-plate G to any desired angle without removing its inner edge from the point of proximity to which it is set. In other words, the

.outer edge of the rest-plate turns on a circle the center or axis of which is coincident with the inner chamfered edge of the rest-plate, and

that said edge (the upper part) coincides with the axis of the block F, so that no matter to what angle of inclination the body of the restplate may be adjusted or turned by means of the bolt 9 in slot 1; of support E, it is evident that the inner edge will retain its relative proximity to the periphery of the stone. When turned to the desired angle of inclination, the rest-plate may be secured in that position by means of the hand-lever H, which is eccentrically secured or pivoted to the eye of the bolt 9 by means of a pin passing through the lugs or cars m, formed on the end of the lever. As shown, the pin is passed through the lugs m at a point to one side of their centers; but it may be passed directly through thecenter of the lugs and the ends of the same sloped or shaped to form a cam-surface with equally good resuit in the operation of the device. There is a washer, is, on the bolt 9, below the support E, against which the cam works.

lhe operation is as follows: The hand-lever H is forced down from the semi-horizontal position shown in Fig. 2 to a vertical position, which relieves the pin of the downward pressure exerted on the same by removing the end of the lever or the surface formed on the same from its contact with the washer it, or the lower side of the support E, if the washer is.

not used, and the lever is then moved forward or backward, sliding the bolt g in the slot 1) until the rest-plate G is tilted to the desired angle of inclination, when the hand-lever is brought to a horizontal position, as shown in Fig. 2, or as near a horizontal position as the cam-surface will permit, which will have the effect of drawing down the bolt and clamping the block F in place, thus seeming the rest plate in the desired angle in a very short space of time.

I do not desire to be limited to the exact construction herein described, as it is obvious that the device may be altered or changed in minor particulars without departure from the scope of my invention. Forinstance, the same result would be obtained, but in a less perfect degree, by doing away with the lever H and screw-threading that end of the bolt having the eye and running a jam-nut against the lower side of the support on the same to hold up the bolt in its adjusted position.

It is also evident that a curved slot could be formed in the outer side wall of the support E, and the bolt 1 inserted in the side of the block F and passed through said slot, and the lever H attached to the end of the same, and the same result secured.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. The combination, with a grinding-wheel or other grindingsurface, of an adjustable areshaped pivot-block and a rest-plate projecting laterally and substantially in the same plane with the upper or fiat side of said block and having its inner edge on alinecoincidentwith the axis of said block, whereby whatever he the angle ofadjustment of the block the edge of the rest will retain its set proximity to the grindingsurfiice, as set forth.

2. The combination,in agrindiugmachine, of the beam 0, a laterally- 'lrojecting and upwardly curved arm, I), having the slotted curved support 1G, extending at right angles to said arm, the semicircular block F, having the eyebolt 5 projecting from its under side, the restplate G, rigidly secured to said block, and the lever H, eccentrically pivoted to said eyebolt 1 substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

EDRVIN J. ARMSTRONG.

Witnesses:

PHILIP MAURO, G. J. Hnmuon'. 

